Malicious PDF — malware analysis report

Static analysis result for SHA-256 b6c8a015a5c427c9…

MALICIOUS

PDF

34.6 KB Created: 2020-08-08 03:27:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: ebd7dac88b890c2231515a8fd5194af9 SHA-1: a8d065ee940a2f704966bf3d852e6ebb4370043d SHA-256: b6c8a015a5c427c94bedeb0a299df8bf84cb0a2aeaf7576ba13484811ad7c538
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a high number of embedded links, many pointing to Shopify domains, but one critical link redirects to `https://ttraff.com/pify?keyword=larson+algebra+2+workbook+pdf`. This indicates a lure to download a PDF, likely malicious, by disguising it as a workbook. The ML classifier strongly supports the malicious nature of this PDF. No scripts were extracted, but the link farm and redirector are strong indicators of a phishing or malware delivery attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://ttraff.com/pify?keyword=larson+algebra+2+workbook+pdf
    • http://bexaxutu.virginiamatzek.com/uploads/1/3/2/6/132680813/db9bee429845c.pdf
    • http://files.konjstudio.net/uploads/1/3/1/1/131163867/4041e031091ae.pdf
    • http://files.joanosato.org/uploads/1/3/1/1/131164574/6570620.pdf
    • https://cdn.shopify.com/s/files/1/0433/5481/6665/files/witcher_3_reshade.pdf
    • https://cdn.shopify.com/s/files/1/0427/5086/9671/files/liniwetusexoro.pdf
    • https://cdn.shopify.com/s/files/1/0430/5505/5002/files/7536084483.pdf
    • https://cdn.shopify.com/s/files/1/0431/9703/8756/files/55401987868.pdf
    • https://cdn.shopify.com/s/files/1/0432/1122/7300/files/20530052239.pdf
    • https://cdn.shopify.com/s/files/1/0433/3142/0314/files/petem.pdf
    • https://cdn.shopify.com/s/files/1/0437/9567/7346/files/shielding_and_deshielding_effect_in_nmr_spectroscopy.pdf
    • https://cdn.shopify.com/s/files/1/0440/2338/2166/files/96679301462.pdf
    • https://cdn.shopify.com/s/files/1/0428/7060/3932/files/pokemon_emrald_walk_through.pdf
    • https://cdn.shopify.com/s/files/1/0433/3607/3366/files/54660018022.pdf
    • https://cdn.shopify.com/s/files/1/0437/2535/7206/files/jofujuropufizosedupetidi.pdf
    • https://cdn.shopify.com/s/files/1/0433/1231/6584/files/kikonomeni.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000048d8.bin
32e631f6da31edafb9d924221c8f97be171d10669f3eb63bbcd06a9a4aa5bf3c
pdf-font-stream PDF embedded font (sfnt) at offset 0x48D8 5580 bytes
font_01_sfnt_off00005bf7.bin
0c68cb5ae9d49198bbab9b2c81e1d062f08b83cd607d5d6798c1b4164f17fa95
pdf-font-stream PDF embedded font (sfnt) at offset 0x5BF7 9836 bytes